refactor: change separate tools by category

core/stdlib/src/arrays/first/index.ts

@@ -0,0 +1,20 @@
+/**
+ * @name first
+ * @category Arrays
+ * @description Returns the first element of an array
+ * 
+ * @param {Value[]} arr The array to get the first element from
+ * @param {Value} [defaultValue] The default value to return if the array is empty
+ * @returns {Value | undefined} The first element of the array, or the default value if the array is empty
+ * 
+ * @example
+ * first([1, 2, 3]); // => 1
+ * 
+ * @example
+ * first([]); // => undefined
+ * 
+ * @since 0.0.3
+ */
+export function first<Value>(arr: Value[], defaultValue?: Value) {
+    return arr[0] ?? defaultValue;
+}